We analyze photometric observations of the three main-belt asteroids 350 Ornamenta, 771 Libera, and 984 Gretia, conducted over a twelve-year interval. Our data and those of other authors allow us to determine pole and shape models using the lightcurve inversion technique. In all three cases, a single pole solution was obtained without any significant mirror solution: Ornamenta – $P = 9.180\,414$ h, $\lambda_{\rm p} = 184\degr$, $\beta_{\rm p} = -29\degr$ Libera – $P = 5.890\,423$ h, $\lambda_{\rm p} = 64\degr$, $\beta_{\rm p} = -78\degr$ Gretia – $P = 5.778\,025$ h, $\lambda_{\rm p} = 245\degr$, $\beta_{\rm p} = +52\degr$. This analysis and the development of asteroid models increase the set of asteroids with known spin and shape parameters, which consists of only around 100 objects.